Index: include/llvm/CodeGen/SelectionDAG.h
===================================================================
--- include/llvm/CodeGen/SelectionDAG.h
+++ include/llvm/CodeGen/SelectionDAG.h
@@ -678,6 +678,10 @@
   /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
   SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
 
+  /// Convert Op, which must be of float type, to the
+  /// float type VT, by either extending or rounding (by truncation).
+  SDValue getFPExtendOrRound(SDValue Op, const SDLoc &DL, EVT VT);
+
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either any-extending or truncating it.
   SDValue getAnyExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
Index: lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -529,11 +529,11 @@
   EVT VT = N->getValueType(0);
   SDValue Res = GetScalarizedVector(N->getOperand(0));
   if (Res.getValueType() != VT)
-    Res = DAG.getNode(ISD::ANY_EXTEND, SDLoc(N), VT, Res);
+    Res = VT.isInteger() ? DAG.getNode(ISD::ANY_EXTEND, SDLoc(N), VT, Res)
+                         : DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT, Res);
   return Res;
 }
 
-
 /// If the input condition is a vector that needs to be scalarized, it must be
 /// <1 x i1>, so just convert to a normal ISD::SELECT
 /// (still with vector output type since that was acceptable if we got here).
Index: lib/CodeGen/SelectionDAG/SelectionDAG.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -984,6 +984,12 @@
   DbgInfo->clear();
 }
 
+SDValue SelectionDAG::getFPExtendOrRound(SDValue Op, const SDLoc &DL, EVT VT) {
+  return VT.bitsGT(Op.getValueType())
+             ? getNode(ISD::FP_EXTEND, DL, VT, Op)
+             : getNode(ISD::FP_ROUND, DL, VT, Op, getIntPtrConstant(0, DL));
+}
+
 SDValue SelectionDAG::getAnyExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT) {
   return VT.bitsGT(Op.getValueType()) ?
     getNode(ISD::ANY_EXTEND, DL, VT, Op) :
Index: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -364,7 +364,8 @@
 
   EVT ValueSVT = ValueVT.getVectorElementType();
   if (ValueVT.getVectorNumElements() == 1 && ValueSVT != PartEVT)
-    Val = DAG.getAnyExtOrTrunc(Val, DL, ValueSVT);
+    Val = ValueVT.isInteger() ? DAG.getAnyExtOrTrunc(Val, DL, ValueSVT)
+                              : DAG.getFPExtendOrRound(Val, DL, ValueSVT);
 
   return DAG.getNode(ISD::BUILD_VECTOR, DL, ValueVT, Val);
 }
@@ -557,10 +558,9 @@
       Val = DAG.getNode(
           ISD::EXTRACT_VECTOR_ELT, DL, PartVT, Val,
           DAG.getConstant(0, DL, TLI.getVectorIdxTy(DAG.getDataLayout())));
-
-      Val = DAG.getAnyExtOrTrunc(Val, DL, PartVT);
     }
 
+    assert(Val.getValueType() == PartVT && "Unexpected vector part value type");
     Parts[0] = Val;
     return;
   }
Index: test/CodeGen/X86/pr31088.ll
===================================================================
--- test/CodeGen/X86/pr31088.ll
+++ test/CodeGen/X86/pr31088.ll
@@ -0,0 +1,141 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefix=SSE
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx | FileCheck %s --check-prefix=AVX
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+f16c | FileCheck %s --check-prefix=F16C
+
+define <1 x half> @ir_fadd_v1f16(<1 x half> %arg0, <1 x half> %arg1) nounwind {
+; SSE-LABEL: ir_fadd_v1f16:
+; SSE:       # BB#0:
+; SSE-NEXT:    pushq %rax
+; SSE-NEXT:    movss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movaps %xmm1, %xmm0
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    movss %xmm0, (%rsp) # 4-byte Spill
+; SSE-NEXT:    movss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; SSE-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    addss (%rsp), %xmm0 # 4-byte Folded Reload
+; SSE-NEXT:    popq %rax
+; SSE-NEXT:    retq
+;
+; AVX-LABEL: ir_fadd_v1f16:
+; AVX:       # BB#0:
+; AVX-NEXT:    pushq %rax
+; AVX-NEXT:    vmovss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovaps %xmm1, %xmm0
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vmovss %xmm0, (%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; AVX-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vaddss (%rsp), %xmm0, %xmm0 # 4-byte Folded Reload
+; AVX-NEXT:    popq %rax
+; AVX-NEXT:    retq
+;
+; F16C-LABEL: ir_fadd_v1f16:
+; F16C:       # BB#0:
+; F16C-NEXT:    vcvtps2ph $4, %xmm1, %xmm1
+; F16C-NEXT:    vcvtph2ps %xmm1, %xmm1
+; F16C-NEXT:    vcvtps2ph $4, %xmm0, %xmm0
+; F16C-NEXT:    vcvtph2ps %xmm0, %xmm0
+; F16C-NEXT:    vaddss %xmm1, %xmm0, %xmm0
+; F16C-NEXT:    retq
+  %retval = fadd <1 x half> %arg0, %arg1
+  ret <1 x half> %retval
+}
+
+define <2 x half> @ir_fadd_v2f16(<2 x half> %arg0, <2 x half> %arg1) nounwind {
+; SSE-LABEL: ir_fadd_v2f16:
+; SSE:       # BB#0:
+; SSE-NEXT:    subq $24, %rsp
+; SSE-NEXT:    movss %xmm2, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movss %xmm1, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movaps %xmm3, %xmm0
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    movss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; SSE-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    movss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; SSE-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    movss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; SSE-NEXT:    movss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; SSE-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; SSE-NEXT:    callq __gnu_f2h_ieee
+; SSE-NEXT:    movzwl %ax, %edi
+; SSE-NEXT:    callq __gnu_h2f_ieee
+; SSE-NEXT:    addss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Folded Reload
+; SSE-NEXT:    movss {{[0-9]+}}(%rsp), %xmm1 # 4-byte Reload
+; SSE-NEXT:    # xmm1 = mem[0],zero,zero,zero
+; SSE-NEXT:    addss {{[0-9]+}}(%rsp), %xmm1 # 4-byte Folded Reload
+; SSE-NEXT:    addq $24, %rsp
+; SSE-NEXT:    retq
+;
+; AVX-LABEL: ir_fadd_v2f16:
+; AVX:       # BB#0:
+; AVX-NEXT:    subq $24, %rsp
+; AVX-NEXT:    vmovss %xmm2, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss %xmm1, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovaps %xmm3, %xmm0
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vmovss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; AVX-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vmovss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; AVX-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vmovss %xmm0, {{[0-9]+}}(%rsp) # 4-byte Spill
+; AVX-NEXT:    vmovss {{[0-9]+}}(%rsp), %xmm0 # 4-byte Reload
+; AVX-NEXT:    # xmm0 = mem[0],zero,zero,zero
+; AVX-NEXT:    callq __gnu_f2h_ieee
+; AVX-NEXT:    movzwl %ax, %edi
+; AVX-NEXT:    callq __gnu_h2f_ieee
+; AVX-NEXT:    vaddss {{[0-9]+}}(%rsp), %xmm0, %xmm0 # 4-byte Folded Reload
+; AVX-NEXT:    vmovss {{[0-9]+}}(%rsp), %xmm1 # 4-byte Reload
+; AVX-NEXT:    # xmm1 = mem[0],zero,zero,zero
+; AVX-NEXT:    vaddss {{[0-9]+}}(%rsp), %xmm1, %xmm1 # 4-byte Folded Reload
+; AVX-NEXT:    addq $24, %rsp
+; AVX-NEXT:    retq
+;
+; F16C-LABEL: ir_fadd_v2f16:
+; F16C:       # BB#0:
+; F16C-NEXT:    vcvtps2ph $4, %xmm3, %xmm3
+; F16C-NEXT:    vcvtph2ps %xmm3, %xmm3
+; F16C-NEXT:    vcvtps2ph $4, %xmm1, %xmm1
+; F16C-NEXT:    vcvtph2ps %xmm1, %xmm1
+; F16C-NEXT:    vcvtps2ph $4, %xmm2, %xmm2
+; F16C-NEXT:    vcvtph2ps %xmm2, %xmm2
+; F16C-NEXT:    vcvtps2ph $4, %xmm0, %xmm0
+; F16C-NEXT:    vcvtph2ps %xmm0, %xmm0
+; F16C-NEXT:    vaddss %xmm2, %xmm0, %xmm0
+; F16C-NEXT:    vaddss %xmm3, %xmm1, %xmm1
+; F16C-NEXT:    retq
+  %retval = fadd <2 x half> %arg0, %arg1
+  ret <2 x half> %retval
+}